1287912340 has 192 divisors, whose sum is σ = 3388573440. Its totient is φ = 404213760.

The previous prime is 1287912313. The next prime is 1287912383. The reversal of 1287912340 is 432197821.

It is a self number, because there is not a number n which added to its sum of digits gives 1287912340.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7444494 + ... + 7444666.

It is an arithmetic number, because the mean of its divisors is an integer number (17648820).

Almost surely, 2^1287912340 is an apocalyptic number.

1287912340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1287912340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1694286720).

1287912340 is an abundant number, since it is smaller than the sum of its proper divisors (2100661100).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1287912340 is a wasteful number, since it uses less digits than its factorization.

1287912340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362 (or 360 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 1287912340 is about 35887.4955938695. The cubic root of 1287912340 is about 1087.9996812373. Note that the first 3 decimals are identical.

It can be divided in two parts, 128791 and 2340, that added together give a palindrome (131131).

The spelling of 1287912340 in words is "one billion, two hundred eighty-seven million, nine hundred twelve thousand, three hundred forty".